2020 33 CFR 173.1 – Purpose; preemptive effect

2009 33 CFR 173.1 – Purpose

2010 33 CFR 173.1 – Purpose

2014 33 CFR 173.1 – Purpose; preemptive effect

2015 33 CFR 173.1 – Purpose; preemptive effect

2016 33 CFR 173.1 – Purpose; preemptive effect

2019 33 CFR 173.1 – Purpose; preemptive effect